The present invention relates generally to switches and electrical charge distribution, and more specifically to a method and device for reducing continuous electric charge distribution in a vehicle.
Normally, in a vehicle motorized by an internal combustion engine, a battery is used to provide operating power for starting the engine, for igniting fuel in the cylinders and for running vehicle accessories such as lighting, information systems and entertainment systems. While these duties have different electrical current requirements, the amperage required for starting the engine far exceeds the amperage required for maintaining the other functions.
The starting circuit of a vehicle generally includes a battery, a starter contactor and a starter, wired in series. The starter contactor has two contactor terminals and is usually mounted between the battery and the starter. A wire is coupled at one end to the positive battery terminal and at the other end to a first starter contactor terminal. The second starter contactor terminal is then wired to the starter. When the ignition key of the vehicle is turned, the starter contactor is closed, thereby electrically coupling the contactor terminals and supplying the starter with the required starting amperage. Due to the high required amperage, the wire coupling the positive battery terminal to the starter contactor is of substantial diameter; therefore, it is costly.
Furthermore, a battery and a starter contactor of a vehicle are usually not juxtaposed. The greater the separation between the battery and the starter contactor, the greater the continuous charge distribution within the vehicle. That is, as the amount of wire required to couple the positive battery terminal to the starter contactor increases, the distribution of positive charge within the vehicle increases. An increase in the distribution of positive charge within the vehicle can be problematic in accident situations, potentially increasing the risk of fire. Further, such an increase requires multiple protective covers, one at the battery and one at the contactor, for guarding against incidental contact with the continuously live terminals during routine maintenance in close proximity thereto. Regarding the latter point, not only does the positive battery terminal require a protective cover, but a protective cover should be used to shield against incidental contact with the continuously live terminal on the starter contactor.
Contactors for use in circuits demanding delivery of high amperage are generally known. For example, U.S. Pat. No. 5,521,566, which is assigned to the owner of the incident application, discloses a solenoid unit for use in high amperage environments. U.S. Pat. No. 5,521,566 is incorporated by reference in its entirety.
Despite the existence and knowledge of such devices, the art of vehicle electrical circuit switching would benefit from a method and device for eliminating costly manufacturing components and increasing the safety of the electrical distribution system in general.